<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        /* 
        代码规范：
            1、展开式
            2、都是小写
         */
        
        p {
            color: aqua;
            font-size: 50px;
        }
        
        .demo01 {
            color: blueviolet;
        }
        
        #demo02 {
            color: blue;
        }
    </style>
</head>

<body>
    <p>css样式</p>
    <p class="demo01">demo01</p>
    <p id="demo02">demo02</p>
</body>

</html>